Technical Abstract:
This paper provides an update and overview of some of the soybean rust (Phakopsora pachyrhizi) research activities in the United States. In 1995, soybean rust was reported in the U.S. in the state of Hawaii. Soybean rust was not reported in another state until late in the fall season of 2004 in Louisiana after which it was reported in 13 other states (http://www.sbrusa.net/). The first report of the disease occurring on another host in the U.S. was on kudzu in Quincy, Florida in 2004. The introduction of the rust fungus into the continental U.S. was thought be carried via Hurricane Ivan that hit the U.S. mainland in September 2004. In 2005, the fungus was first reported in Florida where it was believed to survive the winter on kudzu that remained green below the frost line. At the end of 2005, rust was reported in nine states (Kentucky, North Carolina, and Texas were new reports). In 2006, the fungus was again first found in Florida and to date rust has been found in Alabama, Florida, Georgia, and Texas. Since the introduction of soybean rust in the U.S, there has been an increase of research activity. This started soon after the first report of rust in Hawaii. A soybean rust workshop was held in 1995 that brought together researchers in the U.S. who had experience with rust and laid the foundation for subsequent research direction for soybean rust research in the U.S. Before soybean rust hit the continental U.S., a review in 2003 outlined the importance of the disease and evaluated the risk of rust to the U.S. soybean crop. This paper summarizes some of the research in the U.S. since 2004. This is not a comprehensive review, but rather highlights what has been published in three main areas of research that includes (i) pathogen biology, (ii) host resistance and (iii) fungicides.